1. Field of the Invention
The present invention relates to a musical sound signal recording/reproducing apparatus if which desired musical sound signals are recorded and the recorded musical sound signals are reproduced in response to the depression of corresponding key on the keyboard.
2. Prior Art
One such conventional apparatus is disclosed in U.S. Pat. No. 4,4461,199, where analog waveforms of musical sounds are sampled at predetermined intervals to be converted into digital data representative of the time varying amplitudes of the waveforms, The digital data is then stored in a memory of the apparatus hereinafter referred to as a waveform memory. This apparatus is designed such that a plurality of waveform data representative of musical sounds with different tones can be stored in the waveform memory and the stored waveform data can be read from the waveform memory according to the pitch and tone information input from the keyboard.
With the aforementioned musical sound recording/reproducing apparatus, when a large number of different waveform data are stored in the waveform memory, a sufficient storage area may not be available for future storage of new waveforms. In such cases, the waveform data for unnecessary sounds is usually erased from waveform memory to increase the storage area for the new waveforms leaving non-consecutive available areas of waveform memory as shown FIG. 14A.
The amount of waveform data depends on the length of time a musical sound is recorded and therefore there may not be enough memory to store a new waveform. Waveform data for one instrument is located in consecutive addresses of the waveform memory and the waveform memory is divided up into different blocks with waveform data for different instruments. For this reason, conventionally, when waveform data of a particular instrument is deleted from the waveform memory, all the waveform data stored in waveform memory is rewritten so that all the waveform data is relocated to lower consecutive addresses as shown in FIG. 14B, and the size of the available area of waveform memory is increased. This kind of data processing is, however, time consuming.